Which poppies are you referring to, oriental poppies or annual poppies? Oriental poppies are perennial and usually take 2-3 years to bloom from seed
or cuttings. They are best planted in the fall so they'll get the cold period they need to bloom. Annual poppies are best started directly outdoors because they don't transplant well. Scatter the seeds
where you want them in late winter/early spring
, then thin them out when they germinate. Mine usually start blooming in late April. They reseed well, so you may never have to start more.